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Platform guide

PDQ follows a layered architecture where data flows through three stages — from raw source extraction to a modelled warehouse. Each layer has a clear responsibility and a well-defined handoff to the next.

DATA SOURCES ──► INGEST ──► DLS ──► DWA
LayerFull NameResponsibility
INGESTIngestionExtract data from source systems (databases, APIs, files) and land it in the data lake
DLSData Lake ServiceOrganise, archive, profile and publish raw data through the storage zones
DWAData Warehouse AutomationModel, map and transform data into structured warehouse models

QPI is not a fourth stage. It is the framework's data quality engine: SQL controls run against data in DWA, placed on Published, Core and Business. It reports, and cannot block a load or stop downstream work. It is documented with DWA.


The deep dive, layer by layer​

INGEST layerConnection types, export types and strategies, scheduling, column selection, transformations, destination paths and the sourcefile structure.
DLS layerThe storage zones and their configuration, the DLS pipeline, publish patterns and the considerations behind them.
DWA layerModels and attributes, source-to-target mappings, transformations, relationships, worked modelling scenarios — and QPI.

This page used to carry all three, plus QPI, in a single tab set. The tabs hid their contents from the table of contents and from any deep link, which is why each layer now has its own page.


How the layers connect​

Source Systems → INGEST

Source systems are registered with a connection type (Database, API, File, Custom, or Manual). Each system can have one or more source exports that define how data is extracted — what to query, which columns to include, how often to run, and what output format to produce.

INGEST → DLS

Exported data lands in the Landing Zone. From there, the DLS pipeline archives it to the Raw Zone, processes it through DLS Workers, standardises it into the Trusted Zone, and profiles it in the Profile Zone.

DLS → DWA

Trusted data is synced/published into the Published Zone, where it becomes available for warehouse modelling. The DWA layer maps source fields to model attributes along the model chain: Published → Base → Core → DM.

DWA and QPI

Quality checks are placed on the layers DWA loads. Mapping coverage percentages, field-level governance flags and data profiling results give continuous feedback on pipeline health — reported, never enforced.


Zone architecture​

Data passes through a series of storage zones, each with a specific purpose:

┌──────────┐    ┌──────────────┐    ┌─────────────┐    ┌───────────────┐
│ Landing │ ──►│ Raw Archive │ ──►│ Trusted │ ──►│ Published │
│ Zone │ │ Zone │ │ Zone │ │ Zone │
└──────────┘ └──────────────┘ └─────────────┘ └───────────────┘
Temporary Immutable Standardised Query-ready
staging audit trail format tables

Profile sits alongside Trusted rather than after it. Nothing is filtered out between the zones — a deviation against the data contract is recorded, not blocked, so a shortfall in the counts means something is stuck rather than discarded. See What the platform records, and what it stops.

Zone names are configurable in Settings, so an installation may display its own labels. Paths follow a convention:

[ZoneName]/[System]/[Filename]/[YYYY]/[MM]/[DD]/

Landing takes no date tokens. The zone configuration in full is on the DLS layer page.


Model tiers (DWA)​

The warehouse chain runs Published → Base → Core → DM:

TierAlso known asPurposeExample
PublishedBronzeThe SQL-readable landing point for a delivery, read straight from the trusted zoneOne table per sourcefile
BaseEnsemble ModelIntegrate data from multiple sources with consistent rulesMerge CRM + ERP customer records
CoreIntegrated, SilverFinal deduplicated business entities for consumptionClean Customer, Order, Product tables
DMData Mart, Gold, BusinessModels shaped for a specific analytical use caseA sales star schema

The console still labels the last step Data Mart in Data Lineage. See the model chain for the full synonym table, and why Stage is no longer one of these names.


Terminology​

Every term the platform uses is defined once, in the Glossary. This page used to carry its own table of eight of them, which is how they came to be defined twice and differently.


Next steps​